Ulad Ramanovich

Do you know the newsletter with weekly sharing what happened in the AI or Web development?

I’m trying to find newsletter with analysis what happened for the last week, instead of raw links

#frontend #ai #wevdevelopment #react #nodejs

The `nyc` npm package lets you merge coverage reports from different test jobs into one comprehensive report. Here's how it works:

Tired of slow Jest tests? I cut my test suite time by 67% with these two simple tricks:

1. Add `maxWorkers=50%` to utilize available CPU
2. Implement `shard` to split and run tests in parallel across multiple jobs

The big challenge? Collecting coverage data from separate jobs. Solution below

Senior devs spend 20% of time on code reviews. If you don't, either you're not senior or your team culture needs rework.

Good code reviews:
- Catch bugs before they cause outages
- Share knowledge across the team
- Build better architecture through diverse perspectives

Create a template and do this without thinking :)

For me, it was to have content prepared in advanced

What is your next action when you have an incident and the last PR in the list this one?

Probably author refer to React Server Components where you can render html on server and send it to client.
Nothing wrong with it, because render on server is faster

Confusing by word 'token' when working with AI? Me too 🤔

I spent time understanding how it's calculated, here's simple math:

- Token ≠ word
- 1 word ≈ 1.3token
- 1 tweet ≈ 35 tokens
- Emojis cost extra tokens

shorter words = fewer tokens = lower costs

Skipping tests to save time? Think twice.
While writing tests feels chore, the real cost hits during refactoring.

Use AI for basic tests, but guide it - create mocks & define key scenarios. Keep logic simple, and review all the code produced by AI.

Future you will thank you

You're missing one primary concept when coding with AI.

AI doesn't own the code, the person who approved this code is the owner of the code.

AI is a tool - your expertise in reviewing, validating & owning the implementation is what matters

5/5 Remember: abstract your database logic, centralize configurations, and keep your testing patterns consistent.

4/5 Testing becomes trivial:

- Unit tests: mock DataService
- E2E: use TestDatabaseService with Fishery
- No need to mock individual repositories
- Clean, reusable test data

3/5 Core components:

1. Base Repository - shared database operations
2. Entities - database structure
3. DataService - single entry point
4. Factories - test data generation

2/5 The key is centralizing all database logic in one place.
Create a data-access module that:
• Acts as a single source of truth
• Handles all database operations
• Provides clean testing interfaces
• Manages multiple databases

1/5 How to manage database access in monorepo with NestJS?

I faced this problem a few times:
• Duplicated database logic
• Multiple connection configurations
• Inconsistent testing patterns
• No clear structure

Let me explain how I fixed this with the Data-Access Pattern 🧵
#NestJS #nodejs #webdevb

🐳 Next.js Docker build tips:

1. Split into build/run stages - speeds up builds & enables layer caching
2. Use non-root user for runtime - prevents root access if app is compromised

#Docker #Nextjs #Webdev

4 ways to adapt AI for business needs:

1. Pre-training: Needs massive data, expensive
2. Prompting: Cost-effective, learn it first!
3. Fine-tuning: 1000+ examples for good results
4. RAG: Use your docs as context

Start simple, scale as needed

#AI #LLM

This is env management I bring for each project. Don't rely on process.env directly - use Zod validation instead.

Type-safe + clear errors = no more missing configs

#TypeScript #WebDev #nodejs

Will AI replace your job? 🤔

AI isn't replacing jobs directly - it's automating tasks. Think of it as a tool that helps process work faster, not a robot employee.

Humans still handle complex cases, AI handles repetitive ones. 🤖

70/30 AI Engineering Rule

The 70/30 rule of AI coding: While AI can scaffold 70% of your code, the crucial 30% requires deep engineering expertise.
Best practice: Use AI as a drafting tool, maintain atomic conversations, and own your code through meaningful review.

#AI #SoftwareDevelopment

But what you use for as AI assistance? (Outside of code editor)

🎨 Building new website? Here's a harsh truth:

Most projects fail not because of dev speed, but waiting for "perfect design"

Quick win:
- Ship minimal design in 2 weeks
- Test with real users
- Iterate based on feedback

Stop guessing what users want.

#buildinpublic

Post-interview clarity hit me hard today 💡

Spent 2 weeks learning algorithms, only to get asked about building an actual product feature. Classic over-preparation for the wrong battle.

Lesson: Always check type of interview you're participating. The interview format tells you what you need to know

For me 2nd looks better. Idk exact reasons but it feels like priority of blocks in the second option is better

GitHub - pubkey/broadcast-channel: :satellite: BroadcastChannel to send data between different browser-tabs or nodejs-processes + LeaderElection over the channels https://pubkey.github.io/broadcast-channel/ :satellite: BroadcastChannel to send data between different browser-tabs or nodejs-processes :satellite: + LeaderElection over the channels https://pubkey.github.io/broadcast-channel/ - GitHub - p...

Here's the library I used 👇

broadcast-channel https://buff.ly/2UEqfB8

Multiple tabs sending same requests? Been there 🔧

Solution: Leader Election pattern!
- Tabs form a team
- Pick ONE leader tab
- Only leader makes API calls
- If leader closes, new one steps up

Used broadcast-channel lib. Now instead of 5 requests → just 1

#frontend #javascript

Multiple tabs sending same requests? Been there 🔧

Solution: Leader Election pattern!
- Tabs form a team
- Pick ONE leader tab
- Only leader makes API calls
- If leader closes, new one steps up

Used broadcast-channel lib. Now instead of 5 requests → just 1

#frontend #javascript

React's Virtual DOM Explained:

Instead of updating the webpage directly, React uses a lightweight copy (Virtual DOM).

Changes? React:
1. Updates copy
2. Compares versions
3. Updates only what's needed

That's why React is fast ⚡️

#ReactJS #frontend

Discovered today Docker Compose profiles and was surprised.

Instead of juggling multiple docker-compose files for prod/dev/test, just add "profiles: [dev]" to your services and run:
docker compose --profile dev up

Perfect for managing different environments in a single file!
#docker

Good tip! Doing it for a while, sometimes even use it as a task list 🙂